1. Field of the Invention
The present invention relates to a monitoring lens apparatus and a monitoring camera.
2. Description of Related Art
In recent times, in, for example, financial institutions, stores for selling commodities and the like, a monitoring camera (monitoring CCTV camera) is widely used. Particularly, in recent years, a demand for a dome type small-sized monitoring camera is increasing.
FIG. 4 is a perspective view showing a dome type monitoring camera 100. Further, FIG. 5 is a sectional view showing a state of attaching the monitoring camera 100 to a ceiling. As shown by FIG. 4 and FIG. 5, the monitoring camera 100 is provided with a dome-like outlook, and includes a base 102, a transparent case member 104, and a monitoring lens apparatus 106 arranged at an inner portion of the case member 104. As shown by FIG. 5, the monitoring lens apparatus 106 is attached to the base 102 to be able to make an angle θ variable relative to the base 102. Further, the monitoring lens apparatus 106 can be rotated relative to the base 102 by constituting a rotational axis by a center line C.
As shown by FIG. 4 and FIG. 5, on an inner side of the case member 104, a cover member 108 is mounted to the monitoring lens apparatus 106. The cover member 108 is provided for covering to conceal the monitoring lens apparatus 106. The cover member 108 is provided with an opening 110 in correspondence with a range of changing the angle θ of the monitoring lens apparatus 106. The cover member 108 can be rotated relative to the base 102 by constituting the rotational axis by the center line C along with the monitoring lens apparatus 106.
An outer periphery of the monitoring lens apparatus 106 is provided with a focus ring 112 for adjusting a focus position, and a zoom ring 114 for adjusting a focal length. The focus ring 112, the zoom ring 114 are provided in correspondence with positions of a focus lens (group), a zoom lens (group) provided to the monitoring lens apparatus 106 and are respectively provided on a front side (object side) and a rear side of a lens barrel of the monitoring lens apparatus 106.
The focus ring 112, and the zoom ring 114 are respectively provided with lock knobs 116, 118. The lock knobs 116, 118 are respectively screwed to engage with the focus ring 112, the zoom ring 114. When the lock knobs 116, 118 are fastened, front ends of the lock knobs 116, 118 are brought into contact with a member at an inner portion to thereby fix rotational positions of the focus ring 112, the zoom ring 114.
When the monitoring camera 100 is installed at a ceiling, a wall face or the like of a store or the like, and a direction of an optical axis of the monitoring lens apparatus 106 is set to a direction, in a state of detaching the case member 104, the focal length, the focus position are adjusted. At this occasion, the cover member 108 is constituted integrally with the monitoring lens apparatus 106, a troublesome operation is needed for detaching the cover member 108, and therefore, the focal length, the focus position are adjusted by inserting the finger tip of an operator from the opening 110 of the cover member 108 and manually operating the focus ring 112, the zoom ring 114. Further, after setting the focal length, the focus position to a desired state, by fastening the lock knobs 116, 118, the focus ring 112, the zoom ring 114 are fixed.
Such a monitoring camera is disclosed in, for example, JP-A-2000-305138, JP-A-2000-209471 and JP-A-2001-45344.
However, the monitoring camera 100 in recent times is downsized, and also the mounted monitoring lens apparatus 106 is downsized. Further, in the small-sized monitoring camera 100, there is brought about a situation in which only a necessary minimum space can be ensured at peripheries of the focus ring 112, the zoom ring 114. Therefore, it is difficult to insert the finger tip to the peripheries of the focus ring 112, the zoom ring 114, and thus focus and zoom cannot be adjusted simply and conveniently.
Particularly, in the small-sized monitoring camera 100, the opening 110 of the cover member 108 is provided with a necessary minimum range (width of about 2 cm through 3 cm) in accordance with a diameter of the monitoring lens apparatus 106. Therefore, it is necessary for the operator to operate the focus ring 112, the zoom ring 114 by inserting the finger from the narrow opening 110 to the inner portion, and a very troublesome operation is needed. Particularly, the zoom ring 114 is arranged on a depth side of inside of the cover member 108, and therefore, a troublesome operation of inserting the finger tip of the operator to a vicinity of the base 102 and rotating the zoom ring 114 is needed.
Similarly, also in operating the lock knobs 116, 118, it is necessary to operate the lock knobs 116, 118 by inserting the finger tip from the narrow opening 110, and therefore, a very troublesome operation is requested. Therefore, it is conceivable that the lock knobs 116, 118 are fastened insufficiently, and there is brought about a concern that the lock knobs 116, 118 are released from being fixed in using the monitoring camera 100, and setting of the focus position, the zoom position is shifted. In such a case, a desired image cannot be provided by the monitoring camera 100.
Particularly, when the angle θ of the monitoring lens apparatus 106 shown in FIG. 5 is small, a space between the base 102 and the monitoring lens apparatus 106 is narrowed, and therefore, the operation of the focus ring 112, the zoom ring 114, the lock knobs 116, 118 becomes further difficult.
Further, even when the monitoring camera 100 is not provided with the case member 104, the cover member 108, there is a case in which the operation of the focus ring 112, the zoom ring 114 becomes complicated. As described above, the operation of the focus ring 112, the zoom ring 114 is carried out after setting the direction of the optical axis of the monitoring lens apparatus 106 to the direction, and therefore, when the monitoring lens apparatus 106 is directed in a direction which is difficult to be operated for a direction of the body, a direction of the hand of the operator, the rings are operated by twisting the hand or the like, and thus a complicated operation is needed. Also in this case, particularly the zoom ring 114 is arranged on the side of the base 102 of the monitoring lens apparatus 106 (depth side in view from the operator), and therefore, the operation becomes difficult.